The primary objective of this project is to isolate and identify the mutagens/carcinogens stemming from the cooking of meats. We have now isolated the primary mutagen from fried beef and have obtained structural information based on mass spectroscopy and nuclear magnetic resonance data. We are currently examining a variety of other cooked foods in order to determine whether this mutagen, the most potent mutagen yet described, is formed in foods other than beef. We are also studying simple methods whereby the formation of mutagen can be reduced. Finally, we are purifying a second highly mutagenic principle from beef.